Just before Hurricane Milton slammed into Florida as a Category 3 storm on Wednesday, many people reported that the sky above them turned a sinister purple hue. A sign of the apocalypse? Well, yes, actually—the climate catastrophe we’ve made for ourselves. But it’s still a natural phenomenon with a scientific explanation.
Light and Color
Visible light is a narrow band of the electromagnetic spectrum with wavelengths from 700 to 380 nm. (Nanometers are billionths of a meter.) Within this range, our eyes interpret different wavelengths as different colors: red, orange, yellow, green, blue, indigo, and violet, in order from longest to shortest. (AKA: the rainbow.)
Actually, we have only three color sensors